Downtown commuters will be spending more time on city streets when the I-70/71 corridor is rebuilt.

Construction starting in 2011 is planned to untangle the overlapping freeways, limit ramps and provide more room both on the freeways and on city streets that could in turn spark a building boom along Downtown's southern edge.

The Ohio Department of Transportation has $525 million earmarked to rebuild I-70 through Downtown and I-71 north to I-670. Engineers say they can expand the number of highway lanes on both stretches in the corridor and eliminate much of the confusion and congestion caused by traffic entering and exiting the highway. Some of the traffic in the corridor would be directed to streets redesigned to handle the additional cars and trucks.

The scheme relies upon two pairs of one-way streets to usher vehicles into and out of Downtown.

On the eastern edge along I-71, Lester Drive will expand to carry southbound traffic and a feeder street will be built to connect Parsons Avenue with the freeway northbound. Paralleling I-70 on the north, Mound Street will be one-way westbound and Fulton Street will be one-way eastbound.

"The whole thought process is being reversed," ODOT managing engineer Thom Slack said. "Instead of building the freeway and then working in the city streets, we're looking from the city streets down to make the freeway fit it."

Columbus City Councilwoman Maryellen O'Shaughnessy said drivers will use collector streets only long enough to get to their usual routes. Mainstay roads such as Spring and Long going east-west and 3rd and 4th streets going north-south will still take most of the Downtown traffic.

"We did the Downtown circulation study in conjunction with this," she said. "It's an opportunity to get more distribution through the grid."

ODOT said that redesigning the highways will give them enough room to expand Lester Drive without taking much land and no buildings. Slack said engineers are hoping not to take any buildings along the east side of Parsons.

Along the southern edge of Downtown, however, a reconnected Mound between 5th Street and Grant Avenue would wipe out the parking lot for Americana Apartments and cut a swath through some Franklin University lots.

The street changes also could turn surface parking lots and empty buildings into attractive investments.

Joe Saloom, chief executive officer of JDS Management, said making Mound a collector street reinforces the company's development push in the southeastern corner of Downtown.

JDS has built offices, restaurants and residential property along Main and Mound. Within a year, it will build apartments in the area and has plans for a "boutique hotel" within five years.

"Our plans to make the Market Exchange district an integral part of Downtown … have just been validated," Saloom said.

ODOT officials cited a 2006 city study that projected 7,500 jobs generating $9 million a year in tax revenues if Mound and Fulton were to serve as gateways to I-70 and I-71. But the study strongly recommended that both be two-way streets.

Two-way traffic slows travelers and makes turns into shops or parking garages easier, according to the study's authors, Bay Area Economics.

Slack defended the one-way streets. "We don't see people using Mound and Lester as their wind tunnels to get in and out of Downtown," he said.

Gordon Gough and his wife moved to their Renaissance condo at Mound and 3rd in 2004.

"Part of the concern being a Downtown homeowner is parking," Gough said. "We've got a one-car garage that my wife uses and I park overnight at the meters. I guess that will be a concern to me if they take the parking away."

If it goes the way ODOT recommends, the I-70/71 corridor would have five lanes in each direction: two dedicated to I-71 traffic, two to I-70 traffic and a single center lane for both.

I-71 between I-70 and I-670 would expand to three through lanes in either direction, Slack said.

ODOT will host meetings from 5 to 7 p.m. Monday and Wednesday at the Columbus Board of Health, 240 Parsons Ave.

Later this month, ODOT will take comments on possible caps over the freeways that could support buildings, parks, enhanced bridges and walkways.

The department has identified 12 possible locations for caps like the one on N. High Street over I-670.

In July, ODOT will seek federal approval of the plans and begin detailed work on the project.

Work in the corridor is expected to take through 2015. Rebuilding the I-70/I-71/Rt. 315 interchange west of the Scioto River would begin in 2015 or later, officials said.

Once completed, motorists will use the collector roads and ramps to flow through Downtown from the freeways.

Those heading south on I-71 could exit at Spring and use Lester to connect with a cross street or continue to Main.

Heading out of town, Spring Street will connect to I-71 northbound and I-670 east toward the airport. Motorists also will be able to enter the freeway heading north at Main Street.

Those coming from the east on I-70 could exit on Parsons Avenue to reach Children's Hospital and the east side of German Village. Or they could continue on to the exit that will connect with westbound Mound.

"We have it set up that either by Parsons or Main you can get to and from all directions on the freeway," Slack said.

From the west, motorists could exit at Front Street to reach eastbound Fulton Street. Motorists also have the option of staying on the freeway and exiting at Parsons Avenue.

Heading west from Downtown, Mound will be extended over the river, with lanes dedicated to go to Rt. 315, I-71 or I-70, Slack said.

ODOT doesn't anticipate having to totally shut down the freeway system during construction.

"We will have selective closures and reduction of lanes, but I don't see closing the freeway," Slack said.

Toward the end of the construction, ODOT may close the freeway's lanes in one direction and detour traffic to I-670, Rt. 104 or a combination of interstates.